As shown in the FIG. 1 of the current marketing conventional pressurized cleaning apparatus for spraying and washing the vehicle comprises a water sprayer 1, a portable tank 2 and a compressing diaphragm pump 10. Its features are that the small compressing diaphragm pump 10 can be put into the portable tank 2 and power supply can be taken from the existing 24 volt DC of the cigar-lighter in the vehicle as well as convenient availability of water source everywhere for feeding the portable tank 2 so as to move outdoor for doing the job of spraying and washing the vehicle. For operation of such conventional compressing diaphragm pump 10, via water entry 61 on the upper hood 60 of the compressing diaphragm pump 10 by way of water intake conduit 3, the tap water W is first sucked into the portable tank 2, where the tap water is converted into pressurized water, then sent to the water sprayer 1 via water outtake conduit 4 for spray application. Therefore, the function of the compressing diaphragm pump 10 will primarily affect the operation and the pressure stability of the output water of such cleaning apparatus.
However, two drawbacks exist in the operation procedure of such conventional cleaning apparatus: A. residual air bubbles: the water is poured into the portable tank 2 for refilling when water is run out, the remaining air in the some parts, especially the water intake conduit 3, of such compressing diaphragm pump 10. During next operation, the remaining air will mix with water as air bubbles and get into the operating parts, especially the upper hood 60, of such compressing diaphragm pump 10 to adversely affect the total function, namely jerking vibration of the parts and intermittent instability of the water pressure, which results in harmful load to integral apparatus with shortening service lifetime for long term operation. Thus, how to expel the residual air bubbles mixing in the water during refilling the water becomes the critical problem of such apparatus.
B. abnormal pressure: the phenomena of abnormal pressure will happen in association with increase of the operating time and frequency of such compressing diaphragm pump 10. To understand the cause of the abnormal pressure, the structural and operation functions of each component in the compressing diaphragm pump 10 should be penetrated as below:
As shown in the FIGS. 2 to 6, the conventional compressing diaphragm pump 10 comprises a motor 11, a upper hood chassis 12 disposed along the top of the output shaft not shown in the figures of said motor 11 with plural screw bores 13 being formed on its outer rim, a diaphragm 20 covering said upper hood chassis 12, a piston valve 30 inset in said diaphragm 20, a plastic anti-backflow plastic gasket 40 with three piston slices 50 closely fixed on said piston valve 30 respectively and a upper hood 60 with plural perforated bore 63 being formed on its outer rim, wherein multiple wobble wheels 14 are pivoted on said upper hood chassis 12 to serve as the pumping action in manner from axial reciprocal wobbling movement being driven by the output shaft of said motor 11. By running bolts 5 through all of the corresponding screw bores 13 on said upper hood chassis 12 and perforated bore 63 on said upper hood 60, the whole compressing diaphragm pump 10 is completely integrated (as shown in the FIG. 4).
For said diaphragm 20, a gasket groove 21 is configured on its top peripheral rim and three convex humps 22, each of which being stacked by an eccentric piston pushers 23 respectively, are disposed thereon in corresponding with said three wobble wheels 14. By means of each screw 24 running through each corresponding perforated bore 221 on the convex humps 22 and each perforated bore 231 on the piston pushers 23, each piston pushers 23 and convex humps 22 together with diaphragm 20 is securely screwed on each corresponding wobble wheels 14 (as shown in the FIG. 4) so that all these said components act in simultaneous axial reciprocal wobbling movement with certain displacement (as indicated by dash-line in the FIG. 4).
As further shown in the FIGS. 2 and 4 through 6, said piston valve 30 mainly comprises a hemispherical water discharge base 31, which being upwardly embedded in its central region towards the upper hood 60, and three water inlet ports 35, each of which being respectively disposed beneath of said water discharge base 31 with equal space of 120° inclined angle each other. Wherein, said water discharge base 31 is configured by a orientating hole 32, which being formed in the center thereof, and three separating grooves 33, which being radial split with equal space of 120° inclined angle each other so that three isolated zones being formed in between with plural water discharge spouts 34 shaped therein; said water inlet port 35 is configured by a orientating hole 36 and plural water inlet slots 37 thereon. Said anti-backflow plastic gasket 40, which being unitarily molded by soft elastic material into hollow hemi-spheroid, comprises a central downwards orientating stem 41 and three radial separating rib panels 42, each of which being equally spaced by 120° inclined angle each other, as well as three projecting panels 43 extended out thereof. By simultaneously infixing said orientating stem 41 into the corresponding orientating hole 32 and inserting each projecting panel 43 into each corresponding separating groove 33 on the water discharge base 31, all the water discharge slots 34 in each of three isolated zones of the water discharge base 31 are completely blocked by the anti-backflow plastic gasket 40 in close seal manner around the circumferential rim (as shown in the FIG. 4). Each of said piston slice 50, which has a rigid central orientating stem 51 formed upwardly, is unitarily molded by soft elastic material into inverted flare shape with convex arched outer surface and concave curved inner surface. By inserting said orientating stem 51 into each corresponding orientating hole 36 on the water inlet port 35, all the water inlet slots 37 are completely blocked by the piston slice 50 in close seal manner around the circumferential rim (as shown in the FIGS. 4 and 5); Wherein, plural low pressure chambers 6 are respectively formed between the concave curved inner surface of said piston slice 50 on each water inlet port 35 of the piston valve 30 and the corresponding piston pusher 23 of the diaphragm 20 with one end whereof connecting to the corresponding water inlet slots 37 (as shown in the FIG. 4).
As further shown in the FIGS. 1 and 2 through 4, said upper hood 60 with plural perforated bore 63 formed on the peripheral rim thereof, mainly comprises an water inlet orifice 61 on the external rim, a water exit port 64 in the central top with an internal water outlet orifice 62 therein and an external pressure switch vessel 65 connected thereon for mounting a pressure switch P sold in the current market. Wherein, a ramp groove 66 is configured at the bottom side thereon so that its peripheral rim closely encompasses the piston valve 30 and securely anchors on the gasket groove 21 of said diaphragm 20 in matching manner; an central annular groove 67 is downwardly configured inside of the ramp groove 66 for closely affixing with the water discharge base 31 of said piston valve 30 in matching manner so as to create a pressurized chamber 7 in between (as shown in the FIG. 4).
For practical operation, please refer to FIGS. 1, 7 and 8, due to axial reciprocal wobbling movement of the piston pushers 23 driven by the wobble wheels 14, the water W getting into the water inlet orifice 61 of the upper hood 60 from the portable tank 2 via the water intake conduit 3 (as illustrated by arrow head in the FIG. 7) will bear alternate sucking and pushing force of pumping action, namely; If the piston pushers 23 wobbling downwardly away the piston slice 50, the piston slice 50 is simultaneously pulled downwardly away the water inlet port 35 by the sucking force and draws the water W getting into the low pressure chamber 6 orderly via water inlet orifice 61 and water inlet slots 37 (as illustrated by each arrow head in the FIG. 7), in which the water W is firstly pressurized into water W of middle pressure; If the piston pushers 23 wobbling upwardly towards the piston slice 50, the piston slice 50 is simultaneously pushed upwardly towards the water inlet port 35 by the pushing force and thrusts the water W in the low pressure chamber 6 getting into the pressurized chamber 7 via water discharge spouts 34 (as illustrated by each arrow head in the FIG. 8), in which the water W is secondly pressurized into water W of high pressure; By reiterating such alternate sucking and pushing force of pumping action, the pressure of the water W in the pressurized chamber 7 will be escalated up to 80 psi˜100 psi for practical spraying and washing use or other compatible task requirements in the water sprayer 1 orderly via the water outlet orifice 62 and water exit port 64 in the upper hood 60 as well as water outtake conduit 4 connected thereto.
However, there is a serious drawback in the anti-backflow plastic gasket 40 designs that causes unfavorable effect in the operation of the compressing diaphragm pump 10. As depicted on the foregoing description and shown in the FIG. 5, the anti-backflow plastic gasket 40 is unitarily molded by soft elastic material into hollow hemi-spheroid to be used to cover up on all the water discharge spouts 34 of the piston valve 30, whose associated water inlet port 35 in conjunction with piston slice 50 being driven by the axial reciprocal wobbling movement of the piston pushers 23 for alternate sucking and pushing force of pumping action with finite displacement. Due to the flexibility of the material and the uneven hemispherical shape, not only the effect of water discharging is reduced by the limited displacement in pumping action but also the sealing effect in sucking action becomes unsatisfactory. Thereby, both of the quantity and the pressure in the output water are decreased. Such undesirable defective sealing effect in the anti-backflow plastic gasket 40 becomes worse in aging effect of material owing to the deformation δ getting bigger and results in “abnormal pressure” issue (as shown in the FIG. 6).
In order to solve the abnormal pressure issue mentioned above from the deformation of the anti-backflow plastic gasket 40, the inventor of the present invention improved the design thereof and registered the patent application to the USPTO at Oct. 26, 2005 with application Ser. No. 11/258,027 (published number of US2006/0090642) as archived. As shown in the FIGS. 9 through 12, the structure of the improved compressing diaphragm pump 10 is to transform both of the anti-backflow plastic gasket 40 and associated water discharge port 71 into planar form instead of original hemispherical shape. Coordinating with such planar conversion of the water discharge port 71 in the piston valve 70, a orientating lump 72 with a orientating hole 73 is formed in the center of the water discharge port 71; Three isolated zones with plural water discharge holes 74 of each zone are formed in equal space of 120° inclined angle each other with said orientating lump 72 as center. On the peripheral rim against the corresponding three isolated zones, three water inlet ports 75 are respectively disposed beneath of said water discharge port 71 with a central orientating hole 76 and plural water inlet slots 77 thereon. Besides, the anti-backflow plastic gasket 80 is configured as planar tri-valvular blade shape to completely cover up on the water discharge port 71 with three radial elongate rifts 81 being equally spaced by 120° inclined angle each other so that each valvular blade exactly attaches and blocks each corresponding water discharge hole 74 on the water discharge port 71; In the center of the anti-backflow plastic gasket 80, a orientating aperture 82 is created with a orientating rim 83 beneath thereof (as shown in the FIG. 10).
For practical assembly, as further shown in the FIGS. 10 and 11, by means of aligning the clutch rim 83 of the anti-backflow plastic gasket 80, the orientating aperture 82 is firstly inset into the orientating lump 72 of the piston valve 70, then the anti-backflow plastic gasket 80 and the piston valve 70 are firmly united by inserting the T-shaped orientating stem 90 into the orientating hole 73 of the piston valve 70.
Please refer to the FIG. 12, not only the “abnormal pressure” issue is significantly improved but also the deformation associated is moderated after a long term trial use of the modified piston valve 70 and anti-backflow plastic gasket 80. However, for a period of trial use, new issues are found as below: A. the integration between piston valve 70 and anti-backflow plastic gasket 80 jointed by the T-shaped orientating stem 90 becomes loosening. B. the strength of the valvular blades turns into rather weakening. C. the slight deformation of the piston slice 50 due to aging still exists. Therefore, the inventor of the present invention constantly studies and researches zealously for the purpose of improving the function and solving the remaining issues of the compressing diaphragm pump 10 mentioned above.